Damage is done, you cant "undo" bleach, its permanent. So sorry. Now you know better.
Bleach removes the color. Sometimes you can redye it to fix the color.
But you can use permanent markers to color bleached carpet fibers or wood or tile stains. Just be patient and color a little at a time, blending colors where it will look more natural. Best wishes! Jewell
What is the 'something'?